Using birth control pills for the first time, should I worry that I haven't gotten my period 3 days into the sugar pills?

This is my first pack ever and I've taken every pill at the same time everyday, used a condom for the first 7 days and read the instructions that came in the box.

My partner and I are very fertile people though so I'm worried that I'm the 1% that still gets pregnant using the pill correctly. I've read that it takes time for the body to adjust to the pills so the late period is normal, but the both of us are really adverse to having children.

Should I do a pregnancy test now or wait till next month if I still haven't gotten my period?

Note: I'm 26, so it can't be teenage hormones being funny.